Motion and bottom track when deploying vessel-mounted Signature ADCPs in the Netherlands
The steel mounting frame and instruments withstood pitch as high as eight degrees and roll as high as six degrees, yielding 100 per cent bottom lock in depths of 2 to 20 m.
Optimal velocity resolution in shallow water
The velocity profile displays a 1 m resolution view of transport in this relatively shallow, gravity-driven channel. A bottom-track-derived seabed at approximately 14 m depth is shown along with correlation and amplitude, which are generally above thresholds (Figure 8).
Conclusion – the Signature250 ADCP is a versatile instrument capable of bridging the gap between coastal and deep waters
These deployments represent success in two very different environments. High-quality, high-resolution current data were captured in the sediment-rich, estuarine regime of the Bohai Strait via a towed, unmanned surface vehicle. Data obtained from a Signature250 mounted to a relatively small vessel was sufficiently detailed to capture variability in the sluggish currents of a shallow navigation channel. Both deployments yielded high-performing bottom track in the presence of motion. The Signature250 can be optimized with 1 m cell sizes in shallower water and 2 m in moderate depths. This makes it a versatile instrument capable of bridging the gap between coastal and deep waters.
Reference: Wang C, Liu Z, Harris C, Wu X, Wang H, Brian C, Bi N, Duan H, Xu J. The impact of winter storms on sediment transport through a narrow strait, Bohai, China. Journal of Geophysical Research: Oceans. May 2020.